Research On Anonymous Communication Models With Privacy Awareness

With the development of Internet technology,network security incidents such as data leakage occur frequently,so privacy protection are increasingly crucial.As one of the important means of privacy protection,anonymous communication technology naturally attracts more and more attention.To enhance the security,anonymity,and communication efficiency of anonymous communication technology,this dissertation studies anonymous technology from two aspects:identity authentication and anonymous communication.Firstly,based on the immutability and transparency of blockchain structure,this dissertation proposes a privacy-aware blockchainbased identity authentication model with strong forward security,which enhances the anonymity and security of users' identity.Then,combined with the strong forward secure privacy-aware identity authentication model,a privacy-aware anonymous communication model is proposed,realizing the anonymous identity authentication of communication members,and improving the efficiency of anonymous communication.The main work of this dissertation is as follows:(1)A privacy-aware blockchain-based identity authentication model with strong forward security is proposed.To solve common modulus attacks in the privacy-aware PKI(Public Key Infrastructure)model,this dissertation proposes a strong forward secure ring signature scheme based on RSA,ensuring the forward security of the user's key,and increasing the backward security.Then,by applying the ring signature scheme to the privacy-aware PKI model,this dissertation proposes a privacy-aware blockchain-based PKI model with strong forward security,and then proposes a privacy-aware blockchain-based identity authentication model with strong forward security.The proposed model realizes the strong forward security of users' keys and improves the security of identity authentication.At the same time,the model realizes the anonymity of authentication,which improves its privacy-aware level.Finally,considering selfish mining attacks in blockchain structure,this dissertation proposes a security detection model.It is applied to the privacy-aware identity authentication model with strong forward security to realize the detection of selfish mining attacks in blockchain and guarantee the security of the identity authentication model.(2)A privacy-aware anonymous communication model is proposed.Firstly,based on Boneh-Boyen scheme and IBE(Identity-Based Encryption)algorithm,this dissertation proposes a new signature algorithm,which not only ensures the security of signature,but also simplifies the computation of signature process and improves the efficiency of signature.Secondly,to solve the shortage of controllability of anonymity in anonymous communication model,by applying the signature algorithm based on IBE to the anonymous communication model,this dissertation proposes a controllable anonymous communication model based on IBE.Combined with the strong forward secure privacy-aware identity authentication model,the identity authentication of communication members is realized.Thus,an anonymous communication model with privacy awareness is obtained.In this model,by preprocessing operation,the identifications are generated and distributed in advance,which reduces the number of downloading operations and decrypting operations in the communication process,improving the efficiency of anonymous communication.Performance analysis and experimental results show that the privacy-aware anonymous communication model realizes the controllability of anonymity,improving the efficiency of communication,and obtains better identity anonymity.